Thunderbirds is a British science-fiction television series created by Gerry and Sylvia Anderson, filmed by their production company AP Films (APF) and distributed by ITC Entertainment. It was produced between 1964 and 1966 using a combination of marionette puppetry and scale-model special effects sequences – a hybrid filming technique known as "Supermarionation". Two series comprising a total of 32 episodes were filmed; production ceased after the Andersons' financial backer, Lew Grade, failed in his efforts to sell the programme to American network television.
Set in the mid-2060s, Thunderbirds is a follow-up to Four Feather Falls, Supercar, Fireball XL5 and Stingray. It concerns the exploits of International Rescue (IR), a life-saving organisation equipped with technologically advanced land, sea, air and space rescue vehicles; these are headed by a fleet of five Thunderbird machines and launched from Tracy Island, a secret base in the Pacific Ocean. The main characters are ex-astronaut Jeff Tracy, the founder of IR, and his five adult sons, who pilot the Thunderbird machines.
Thunderbirds began its first UK run on the ITV network in 1965 and has since been broadcast in at least 66 other countries. Periodically repeated, the series was adapted for radio in the early 1990s and has influenced many TV programmes (including a Japanese remake) and other media. As well as inspiring various merchandising campaigns, it has been followed by two film sequels, a live-action film adaptation and a mimed stage show tribute. A real-life rescue service, the International Rescue Corps, is named after the organisation featured in the series.
Widely considered to be the Andersons' most popular and commercially successful series, Thunderbirds has been praised for its effects (directed by Derek Meddings) and musical score (composed by Barry Gray). The series is well remembered for its title sequence, which opens with an often-quoted countdown by voice actor Peter Dyneley: "5, 4, 3, 2, 1: Thunderbirds Are Go!" A computer-animated remake, Thunderbirds Are Go, premiered on ITV in April 2015.